1. Field of the Invention
The present invention relates to a data delivery system in which a plurality of data delivery units cooperate to deliver data to clients.
2. Description of the Background Art
In keeping with the development of networks and the improved performance of hardwares in recent years, data to be handled are also increasing in capacity. In particular, the spread of multimedia data in which speech, video, text, etc., are handled collectively is pushing this trend of increasing capacity of data. For this reason, as a technique for transmitting, receiving and processing a large amount of data at high speed, there is a need for a data supply device capable of storing a large amount of data efficiently and providing data in response to various requests quickly.
One such data supply device is a connection-oriented data delivery system formed by a plurality of processors connected through a network. In this system, the conventionally adopted scheme for determining a processor to carry out the data delivery includes the following.
(1) Provide a control processor for determining a processor to carry out the data delivery.
(2) Fixedly determine a processor to carry out the data delivery according to a state of connection to the network, etc.
However, in the former scheme for providing the control processor, there is a problem that the entire data delivery system will stop and the subsequent data supply becomes impossible when that control processor is disabled. Also, in the latter scheme for determining fixedly, there is a problem that the processor resources cannot be utilized effectively when the processing loads concentrate on a specific processor, because it is impossible to re-distribute the processing loads to the other less loaded processors.